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Hydraulic drive and control system of the cone collecting robot
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作者 孔庆华 刘晋浩 陆怀民 《Journal of Forestry Research》 SCIE CAS CSCD 1999年第4期254-256,共3页
This paper describes the basic structure and design and operation principle of the hydraulic drive and control system with two pumps and two circuits. The manipulator of the cone collecting robot designed is full driv... This paper describes the basic structure and design and operation principle of the hydraulic drive and control system with two pumps and two circuits. The manipulator of the cone collecting robot designed is full driven by hydraulic, which has five freedoms. The computer and electrohydraulic proportion velocity regulating valve were installed to realize open loop serve control for reducing cost and easy application. 展开更多
关键词 Cone collecting Robot Hydraulic system Serve control
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Design and implementation of railway green performance basic data collection system 被引量:1
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作者 Xiangru Lyu Hui Li 《High-Speed Railway》 2023年第4期265-272,共8页
This study addressed the issues related to the collection and management of basic data for railway green performance. A railway green performance basic database has been constructed based on metadata and data exchange... This study addressed the issues related to the collection and management of basic data for railway green performance. A railway green performance basic database has been constructed based on metadata and data exchange schemas. A data classification system has been established from the perspectives of businesses, processes,and entities. A BIM(Building Information Modelling) model data extraction scheme is proposed based on field similarity matching and a document content extraction scheme is proposed based on image recognition. A railway green performance basic data collection system has been developed, achieving efficient collection and integrated management of railway green performance basic data. This system can provide data support for applications such as railway carbon emissions accounting, green cost-benefit analysis, and evaluation of green design solutions. 展开更多
关键词 RAILWAY Green performance Data collection METADATA Data classifcation BIM Image recognition
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Research on Chinese Antarctic Data Directory System^->─Collecting,processing,examining and submitting data directory
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作者 程少华 张侠 +5 位作者 朱建钢 赵卫权 凌晓良 李升贵 方斌贤 赵惠莉 《Chinese Journal of Polar Science》 2000年第1期74-78,共5页
Based on the general framework of ADDS( Antarctic Data Directory System) established by SCAR- COMNAP ad hoc Planning Group on Antarctic data management,the CN- ADDS( Chinese Antarctic Data Directory System) projecti... Based on the general framework of ADDS( Antarctic Data Directory System) established by SCAR- COMNAP ad hoc Planning Group on Antarctic data management,the CN- ADDS( Chinese Antarctic Data Directory System) projectis go- ing on,of which the research and activity keeps to the available method and technique in ADDS development and allows for the Chinese specific status in Antarctic data man- agementas well.Atpresent,authoring and submitting timely Antarctic data directory in China is one of the key issuesthatisto be dealtwith necessarily.This paper aims at studying the technical procedure in collecting,processing,examining and submitting data directory. In additional,italso discusses the efficient collection of data directory, which needs the effort of administrative and technical support. 展开更多
关键词 ADDS CN- ADDS Antarctic Data Directory collecting processing submitting
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Experimental Study on the Resistance and Splash Performances of Water Collecting Devices for Mechanical Draft Cooling Towers
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作者 Guoqing Long Guogang Zhang +3 位作者 Qi Zhang Cuilin Zhao Suoying He Fengzhong Sun 《Fluid Dynamics & Materials Processing》 EI 2023年第7期1789-1801,共13页
In recent years,water collecting systems,with the associated advantages of energy saving and noise reduction,have become the foundation for the development of a scheme to optimize the structure of cooling towers.To ex... In recent years,water collecting systems,with the associated advantages of energy saving and noise reduction,have become the foundation for the development of a scheme to optimize the structure of cooling towers.To explore the feasibility of this approach for mechanical draft cooling towers,a small-scale experimental device has been built to study the resistance and splash performances of three U-type water collecting devices(WCDs)for different water flow rates and wind speeds.The experimental results show that within the considered ranges of wind speed and water flow rate,the pressure drop of the different WCDs can vary significantly.The resistance and local splash performances can also be remarkably different.Some recommendations about the most suitable system are provided.Moreover,a regression analysis of the experimental data is conducted,and the resulting fitting formulas for resistance and splash performance of WCD are reported. 展开更多
关键词 Mechanical draft cooling towers water collecting device resistance performance splash performance fitting formulas
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Spatial distribution order parameter prediction of collective system using graph network
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作者 赵慧敏 王瑞 +1 位作者 赵偲 郑文 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第5期566-572,共7页
In the past few decades, the study of collective motion phase transition process has made great progress. It is also important for the description of the spatial distribution of particles. In this work, we propose a n... In the past few decades, the study of collective motion phase transition process has made great progress. It is also important for the description of the spatial distribution of particles. In this work, we propose a new order parameter φ to quantify the degree of order in the spatial distribution of particles. The results show that the spatial distribution order parameter can effectively describe the transition from a disorderly moving phase to a phase with a coherent motion of the particle distribution and the same conclusion could be obtained for systems with different sizes. Furthermore, we develop a powerful molecular dynamic graph network(MDGNet) model to realize the long-term prediction of the self-propelled collective system solely from the initial particle positions and movement angles. Employing this model, we successfully predict the order parameters of the specified time step. And the model can also be applied to analyze other types of complex systems with local interactions. 展开更多
关键词 order parameter graph network collective system active matter
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Hydrogen inhibition effect of chitosan and sodium phosphate on ZK60 waste dust in a wet dust removal system:A feasible way to control hydrogen explosion
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作者 Yuyuan Zhang Kaili Xu +2 位作者 Jiahuan Li Bo Liu Ben Wang 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2023年第8期2916-2926,共11页
Wet dust removal systems used to control dust in the polishing or grinding process of Mg alloy products are frequently associated with potential hydrogen explosion caused by magnesium-water reaction.For purpose of avo... Wet dust removal systems used to control dust in the polishing or grinding process of Mg alloy products are frequently associated with potential hydrogen explosion caused by magnesium-water reaction.For purpose of avoiding hydrogen explosion risks,we try to use a combination of chitosan(CS)and sodium phosphate(SP)to inhibit the hydrogen evolution reaction between magnesium alloy waste dust and water.The hydrogen evolution curves and chemical kinetics modeling for ten different mixing ratios demonstrate that 0.4wt%CS+0.1wt%SP yields the best inhibition efficiency with hydrogen generation rate of almost zero.SEM and EDS analyses indicate that this composite inhibitor can create a uniform,smooth,tight protective film over the surface of the alloy dust particles.FTIR and XRD analysis of the chemical composition of the surface film show that this protective film contains CS and SP chemically adsorbed on the surface of ZK60 but no detectable Mg(OH)_(2),suggesting that magnesium-water reaction was totally blocked.Our new method offers a thorough solution to hydrogen explosion by inhibiting the hydrogen generation of magnesium alloy waste dust in a wet dust removal system. 展开更多
关键词 ZK60 waste dust Hydrogen inhibition Wet magnesium alloy waste dust collection system CHITOSAN Sodium phosphate
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Lumen-apposing-metal stent misdeployment in endoscopic ultrasound-guided drainages:A systematic review focusing on issues and rescue management
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作者 Elia Armellini Flavio Metelli +4 位作者 Andrea Anderloni Anna Cominardi Giovanni Aragona Michele Marini FabioPace 《World Journal of Gastroenterology》 SCIE CAS 2023年第21期3341-3361,共21页
BACKGROUND The introduction of lumen-apposing metal stents(LAMS)for endoscopic ultrasound(EUS)-guided drainages has marked a turning point in the field of interventional ultrasound and it is gathering worldwide diffus... BACKGROUND The introduction of lumen-apposing metal stents(LAMS)for endoscopic ultrasound(EUS)-guided drainages has marked a turning point in the field of interventional ultrasound and it is gathering worldwide diffusion in different clinical settings.Nevertheless,the procedure may conceal unexpected pitfalls.LAMS misdeployment is the most frequent cause of technical failure and it can be considered a procedure-related adverse event when it hampers the conclusion of the planned procedure or results in significant clinical consequences.Stent misdeployment can be managed successfully by endoscopic rescue maneuvers to allow the completion of the procedure.To date,no standardized indication is available to guide an appropriate rescue strategy depending on the type of procedure or of misdeployment.AIM To evaluate the incidence of LAMS misdeployment during EUS-guided choledochoduodenostomy(EUS-CDS),gallbladder drainage(EUS-GBD)and pancreatic fluid collections drainage(EUS-PFC)and to describe the endoscopic rescue strategies adopted under the circumstance.METHODS We conducted a systematic review of the literature on PubMed by searching for studies published up to October 2022.The search was carried out using the exploded medical subject heading terms“lumen apposing metal stent”,“LAMS”,“endoscopic ultrasound”and“choledochoduodenostomy”or“gallbladder”or“pancreatic fluid collections”.We included in the review on-label EUS-guided procedures namely EUS-CDS,EUS-GBD and EUS-PFC.Only those publications reporting EUS-guided LAMS positioning were considered.The studies reporting a technical success rate of 100%and other procedure-related adverse events were considered to calculate the overall rate of LAMS misdeployment,while studies not reporting the causes of technical failure were excluded.Case reports were considered only for the extraction of data regarding the issues of misdeployment and rescue techniques.The following data were collected from each study:Author,year of publication,study design,study population,clinical indication,technical success,reported number of misdeployment,stent type and size,flange misdeployed and type of rescue strategy.RESULTS The overall technical success rate of EUS-CDS,EUS-GBD and EUS-PFC was 93.7%,96.1%,and 98.1%respectively.Significant rates of LAMS misdeployment have been reported for EUS-CDS,EUS-GBD and EUS-PFC drainage,respectively 5.8%,3.4%,and 2.0%.Endoscopic rescue treatment was feasible in 86.8%,80%,and 96.8%of cases.Non endoscopic rescue strategies were required only in 10.3%,16%and 3.2%for EUS-CDS,EUS-GBD,and EUS-PFC.The endoscopic rescue techniques described were over-the-wire deployment of a new stent through the created fistula tract in 44.1%,8%and 64.5%and stent-in-stent in 23.5%,60%,and 12.9%,respectively for EUSCDS,EUS-GBD,and EUS-PFC.Further therapeutic option were endoscopic rendezvous in 11.8%of EUS-CDS and repeated procedure of EUS-guided drainage in 16.1%of EUS-PFC.CONCLUSION LAMS misdeployment is a relatively common adverse event in EUS-guided drainages.There is no consensus on the best rescue approach in these cases and the choice is often made by the endoscopist relying upon the clinical scenario,anatomical characteristics,and local expertise.In this review,we investigated the misdeployment of LAMS for each of the on-label indications focusing on the rescue therapies used,with the aim of providing useful data for endoscopists and to improve patient outcomes. 展开更多
关键词 Lams misdeployment Endoscopic ultrasound-guided drainage Lams maldeployment Biliary drainage Gallbladder drainage Pancreatic fluid collections Lumen-apposing metal stents
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Dynamics along the epithelial-cancer biointerface:Hidden system complexities
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作者 IVANA PAJIC-LIJAKOVIC MILAN MILIVOJEVIC 《BIOCELL》 SCIE 2023年第11期2321-2334,共14页
The biointerface dynamics influence any cancer spreading through the epithelium since it is documented in the early stages some malignancies(like epithelial cancer).The altered rearrangement of epithelial cells has an... The biointerface dynamics influence any cancer spreading through the epithelium since it is documented in the early stages some malignancies(like epithelial cancer).The altered rearrangement of epithelial cells has an impact on the development of cancer.Therefore,it is necessary to comprehend the underlying biological and physical mechanisms of this biointerface dynamics for early suppression of cancer.While the biological mechanisms include cell signaling and gene expression,the physical mechanisms are several physical parameters such as the epithelial-cancer interfacial tension,epithelial surface tension,and compressive stress accumulated within the epithelium.Although the segregation of epithelia-cancer co-cultured systems was widely investigated,the role of these physical parameters in cell reorganization is still not fully recognized.Hence,this review is focused on clarifying the role that some physical parameters have during cell reorganization within the epithelial cell clusters and cancer spread within co-cultured spheroids.We have applied the developed biophysical model to point out the inter-relations among physical parameters that influence cell reorganization within epithelial-cancer co-cultured systems.The main results of this theoretical consideration have been assessed by integrating the biophysical model with biological and bio-mechanical experiments from the available literature.The epithelial-cancer interfacial tension leads to the reduction of the biointerface area,which leads to an increase in the compressive residual stress within the epithelial clusters depending on the viscoelasticity of the epithelial subpopulation.This stress impacts epithelial rearrangement and the dynamics along the biointerface by influencing the epithelial surface tension and epithelial-cancer interfacial tension.Further,the interrelation between the epithelial surface tension and epithelial-cancer interfacial tension influences the spread of cancer cells. 展开更多
关键词 Collective cell migration Cell compressive residual stress Viscoelasticity Epithelial surface tension Epithelial-cancer interfacial tension Supracellular actin network
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Psychosocial Group Intervention at a Low-Resource Setting Environment for Women Who Are Diagnosed and Treated for Breast Cancer: A Systematic Review
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作者 Motlalepule Lekeka 《Health》 2023年第10期1150-1170,共21页
Africa faces significant challenges in terms of material and personnel resources for oncology interventions. This is particularly evident in South Africa, where resources are divided into high- and low-resource settin... Africa faces significant challenges in terms of material and personnel resources for oncology interventions. This is particularly evident in South Africa, where resources are divided into high- and low-resource settings. High-resource settings cater to those with financial means to access private oncology facilities. However, many breast cancer patients receive care in South Africa’s low-resource settings, such as public hospital oncology clinics. Unfortunately, these settings have limited service providers and fail to offer comprehensive interventions, resulting in poor outcomes. However, recent research has highlighted the significance of socially supportive relationships in promoting healing and overall individual well-being, and spirituality has been identified as a source of positive outcomes in cancer patients. This systematic review paper explores the feasibility of implementing support group cancer care and interventions that incorporate social support networks available in community settings, and spiritual practices facilitated by traditional healers, and religious/spiritual leaders. These interventions can be provided within low-resource settings to women diagnosed with breast cancer. Inclusive participation of spouses, children, and extended family in the support group cancer care can facilitate healing for the entire system. Focusing on the strengths and resources within communities and incorporating these complementary services, can enhance the well-being and quality of life for Black African women diagnosed with breast cancer, despite low-resource settings. This approach acknowledges the potential of community-based support networks and encourages collaboration between various stakeholders, including community health educators, nurses, lay counselors, and community volunteers, to address the complex needs of these patients. 展开更多
关键词 Breast Cancer Low Socioeconomic Status Social Support system The Collective Unconscious Low-Resource Setting Intervention
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Research and Application of Meteorological Response Measures for Civil Engineering and Data Acquisition System
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作者 Dawei XU Zhimin ZHANG Feng PAN 《Meteorological and Environmental Research》 CAS 2023年第3期54-59,共6页
Meteorological conditions have a very important impact on the development of construction projects.In order to assist project site managers to quickly and accurately deal with the engineering risks brought by meteorol... Meteorological conditions have a very important impact on the development of construction projects.In order to assist project site managers to quickly and accurately deal with the engineering risks brought by meteorological conditions,meteorological risk assessment indicators for civil construction are established based on the actual impact of different meteorological conditions on each sub-project of civil engineering.A meteorological intelligent management system is created,and it will select reasonable countermeasures from the integrated existing database and push them to on-site construction managers based on meteorological risk assessment indicators.Through the pre-set construction log module,the managers can give feedback on the application effect of the pushed measures,and achieve the effect of construction data collection,correction and expansion of the existing database. 展开更多
关键词 METEOROLOGY Construction measures DATABASE Information collection Management system
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Design and Implementation of Batch Calibration System for Platinum Resistance Temperature Sensors
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作者 Hui LIANG Tianwen SONG Yun XIAN 《Meteorological and Environmental Research》 CAS 2023年第5期19-23,共5页
Developing a calibration and collection system of platinum resistance temperature sensor using Python language environment can read the information returned by the serial port and automatically generate an"Temper... Developing a calibration and collection system of platinum resistance temperature sensor using Python language environment can read the information returned by the serial port and automatically generate an"Temperature Sensor Calibration Record Table"excel table with the current date as the file name.It can collect data from 10 platinum resistance temperature sensors at once,achieving automation and improving work efficiency. 展开更多
关键词 PYTHON Air temperature sensor COLLECTION
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2023年发表当年被引次数5及其以上的全球棉业相关论文
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作者 杨子山 《中国棉花》 2024年第2期59-62,共4页
2024年1月4日,在Web of Science网站以“cotton”或“Gossypium”为“Title”(文题)检索词查询“Web of Science Core Collection”和“Chinese Science Citation DatabaseSM”数据库中2023年发表文章,选择被引次数5及其以上文章68篇。
关键词 被引次数 COLLECTION 数据库 检索词
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Endoscopic intramural cystogastrostomy for treatment of peripancreatic fluid collection: A viewpoint from a surgeon 被引量:1
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作者 Chen-Guo Ker 《World Journal of Gastroenterology》 SCIE CAS 2024年第6期610-613,共4页
Percutaneous or endoscopic drainage is the initial choice for the treatment of peripancreatic fluid collection in symptomatic patients.Endoscopic transgastric fenestration(ETGF)was first reported for the management of... Percutaneous or endoscopic drainage is the initial choice for the treatment of peripancreatic fluid collection in symptomatic patients.Endoscopic transgastric fenestration(ETGF)was first reported for the management of pancreatic pseu-docysts of 20 patients in 2008.From a surgeon’s viewpoint,ETGF is a similar procedure to cystogastrostomy in that they both produce a wide outlet orifice for the drainage of fluid and necrotic debris.ETGF can be performed at least 4 wk after the initial onset of acute pancreatitis and it has a high priority over the surgical approach.However,the surgical approach usually has a better success rate because surgical cystogastrostomy has a wider outlet(>6 cm vs 2 cm)than ETGF.However,percutaneous or endoscopic drainage,ETGF,and surgical approach offer various treatment options for peripancreatic fluid collection patients based on their conditions. 展开更多
关键词 Pancreatitis Pancreatic pseudocyst Endoscopic cystogastrostomy Surgical cystogastrostomy Peripancreatic fluid collection Fenestration for pancreatic cyst
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Collective Molecular Machines: Multidimensionality and Reconfigurability
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作者 Bin Wang Yuan Lu 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第8期309-340,共32页
Molecular machines are key to cellular activity where they are involved in converting chemical and light energy into efficient mechanical work.During the last 60 years,designing molecular structures capable of generat... Molecular machines are key to cellular activity where they are involved in converting chemical and light energy into efficient mechanical work.During the last 60 years,designing molecular structures capable of generating unidirectional mechanical motion at the nanoscale has been the topic of intense research.Effective progress has been made,attributed to advances in various fields such as supramolecular chemistry,biology and nanotechnology,and informatics.However,individual molecular machines are only capable of producing nanometer work and generally have only a single functionality.In order to address these problems,collective behaviors realized by integrating several or more of these individual mechanical units in space and time have become a new paradigm.In this review,we comprehensively discuss recent developments in the collective behaviors of molecular machines.In particular,collective behavior is divided into two paradigms.One is the appropriate integration of molecular machines to efficiently amplify molecular motions and deformations to construct novel functional materials.The other is the construction of swarming modes at the supramolecular level to perform nanoscale or microscale operations.We discuss design strategies for both modes and focus on the modulation of features and properties.Subsequently,in order to address existing challenges,the idea of transferring experience gained in the field of micro/nano robotics is presented,offering prospects for future developments in the collective behavior of molecular machines. 展开更多
关键词 Molecular machines Collective control Collective behaviors DNA Biomolecular motors
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Magnetic Nonreciprocity in a Hybrid Device of Asymmetric Artificial Spin-Ice-Superconductors
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作者 李冲 黄培源 +15 位作者 王晨光 李浩杰 吕阳阳 岳文诚 袁子雄 李甜雨 涂学凑 陶涛 董思宁 何亮 贾小氢 孙国柱 康琳 王华兵 吴培亨 王永磊 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第6期119-127,共9页
Controlling the size and distribution of potential barriers within a medium of interacting particles can unveil unique collective behaviors and innovative functionalities.We introduce a unique superconducting hybrid d... Controlling the size and distribution of potential barriers within a medium of interacting particles can unveil unique collective behaviors and innovative functionalities.We introduce a unique superconducting hybrid device using a novel artificial spin ice structure composed of asymmetric nanomagnets.This structure forms a distinctive superconducting pinning potential that steers unconventional motion of superconducting vortices,thereby inducing a magnetic nonreciprocal effect,in contrast to the electric nonreciprocal effect commonly observed in superconducting diodes.Furthermore,the polarity of the magnetic nonreciprocity is in situ reversible through the tunable magnetic patterns of artificial spin ice.Our findings demonstrate that artificial spin ice not only precisely modulates superconducting characteristics but also opens the door to novel functionalities,offering a groundbreaking paradigm for superconducting electronics. 展开更多
关键词 artificial COLLECTIVE reciprocal
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Experimental Investigations of Quasi-Coherent Micro-Instabilities in J-TEXT Ohmic Plasmas
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作者 石鹏 庄革 +5 位作者 程芝峰 高丽 周乙楠 刘永 罗景庭 李景春 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第5期47-52,共6页
Quasi-coherent micro-instabilities is one of the key topics of magnetic confinement fusion. This work focuses on the quasi-coherent spectra of ion temperature gradient(ITG) and trapped-electron-mode instabilities usin... Quasi-coherent micro-instabilities is one of the key topics of magnetic confinement fusion. This work focuses on the quasi-coherent spectra of ion temperature gradient(ITG) and trapped-electron-mode instabilities using newly developed far-forward collective scattering measurements within ohmic plasmas in the J-TEXT tokamak.The ITG mode is characterized by frequencies ranging from 30 to 100 k Hz and wavenumbers(k_(θρs)) less than 0.3. Beyond a critical plasma density threshold, the ITG mode undergoes a bifurcation, which is marked by a reduction in frequency and an enhancement in amplitude. Concurrently, enhancements in ion energy loss and degradation in confinement are observed. This ground-breaking discovery represents the first instance of direct experimental evidence that establishes a clear link between ITG instability and ion thermal transport. 展开更多
关键词 ITG mode COLLECTIVE
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Does mesenchymal stem cell’s secretome affect spinal sensory circuits?Implication for pain therapies
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作者 Francesco Ferrini Esri H.Juárez Adalberto Merighi 《Neural Regeneration Research》 SCIE CAS 2025年第1期181-183,共3页
Mesenchymal stem cells(MSCs)are multipotent adult stem cells of mesodermal origin that can be isolated from various tissues,including bone marrow,tooth pulp,adipose tissue,and umbilical cord.MSCs have gained significa... Mesenchymal stem cells(MSCs)are multipotent adult stem cells of mesodermal origin that can be isolated from various tissues,including bone marrow,tooth pulp,adipose tissue,and umbilical cord.MSCs have gained significant attention in regenerative medicine due to their ability to modulate the immune system and favor tissue repair.MSCs enrich the medium in which they are cultivated with a broad range of bioactive molecules,including growth factors,cytokines,chemokines,enzymes,nucleic acids,and extracellular vesicles that collectively compose the MSC secretome.An increasing number of pre-clinical studies suggest that delivering in vivo an MSC-conditioned medium(i.e.,the medium collected from MSC cultures after at least 3 days of exposure)exerts neuroprotective and anti-inflammatory effects in a variety of neurological conditions. 展开更多
关键词 protective clinical COLLECTIVE
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Low-noise and low-power pixel sensor chip for gas pixel detectors
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作者 Zhuo Zhou Shi-Qiang Zhou +8 位作者 Dong Wang Xiang-Ming Sun Chao-Song Gao Peng-Zhen Zhu Wei-Ping Ren Jun Liu Mu-Xian Li Chen Lian Chun-Lai Dong 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第3期142-152,共11页
Topmetal-M2 is a large-area pixel sensor chip fabricated using the GSMC 130 nm CMOS process in 2021.The pixel array of Topmetal-M2 consists of pixels of 400 rows×512 columns with a pixel pitch of 45μm×45μm... Topmetal-M2 is a large-area pixel sensor chip fabricated using the GSMC 130 nm CMOS process in 2021.The pixel array of Topmetal-M2 consists of pixels of 400 rows×512 columns with a pixel pitch of 45μm×45μm.The array is divided into 16 subarrays,with pixels of 400 rows×32 columns per subarray.Each pixel incorporates two charge sensors:a diode sensor and a Topmetal sensor.The in-pixel circuit primarily consists of a charge-sensitive amplifier for energy measurements,a discriminator with a peak-holding circuit,and a time-to-amplitude converter for time-of-arrival measurements.The pixel of Topmetal-M2 has a charge input range of~0-3 k e-,a voltage output range of~0-180 mV,and a charge-voltage conversion gain of~59.56μV∕e-.The average equivalent noise charge of Topmetal-M2,which includes the readout electronic system noise,is~43.45 e-.In the scanning mode,the time resolution of Topmetal-M2 is 1 LSB=1.25μs,and the precision is^()7.41μs.At an operating voltage of 1.5 V,Topmetal-M2 has a power consumption of~49 mW∕cm~2.In this article,we provide a comprehensive overview of the chip architecture,pixel working principles,and functional behavior of Topmetal-M2.Furthermore,we present the results of preliminary tests conducted on Topmetal-M2,namely,alpha-particle and soft X-ray tests. 展开更多
关键词 Charge collection Gas detectors Semiconductor detectors X-ray detectors
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Properties of collective flow and pion production in intermediate-energy heavy-ion collisions with a relativistic quantum molecular dynamics model
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作者 Si-Na Wei Zhao-Qing Feng 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第1期155-169,共15页
The relativistic mean-field approach was implemented in the Lanzhou quantum molecular dynamics transport model(LQMD.RMF). Using the LQMD.RMF, the properties of collective flow and pion production were investigated sys... The relativistic mean-field approach was implemented in the Lanzhou quantum molecular dynamics transport model(LQMD.RMF). Using the LQMD.RMF, the properties of collective flow and pion production were investigated systematically for nuclear reactions with various isospin asymmetries. The directed and elliptic flows of the LQMD.RMF are able to describe the experimental data of STAR Collaboration. The directed flow difference between free neutrons and protons was associated with the stiffness of the symmetry energy, that is, a softer symmetry energy led to a larger flow difference. For various collision energies, the ratio between the π^(-) and π^(+) yields increased with a decrease in the slope parameter of the symmetry energy. When the collision energy was 270 MeV/nucleon, the single ratio of the pion transverse momentum spectra also increased with decreasing slope parameter of the symmetry energy in both nearly symmetric and neutron-rich systems.However, it is difficult to constrain the stiffness of the symmetry energy with the double ratio because of the lack of threshold energy correction on the pion production. 展开更多
关键词 Heavy-ion collision Collective flow Pion production Symmetry energy Relativistic mean field
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Species’ geographical range, environmental range and traits lead to specimen collection preference of dominant plant species of grasslands in Northern China
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作者 Jingya Zhang Cui Xiao +5 位作者 Xiaoyu Duan Xin Gao Hao Zeng Rong'an Dong Gang Feng Keping Ma 《Plant Diversity》 SCIE CAS CSCD 2024年第3期353-361,共9页
Many different factors,such as species traits,socio-economic factors,geographical and environmental factors,can lead to specimen collection preference.This study aims to determine whether grassland specimen collection... Many different factors,such as species traits,socio-economic factors,geographical and environmental factors,can lead to specimen collection preference.This study aims to determine whether grassland specimen collection in China is preferred by species traits(i.e.,plant height,flowering and fruiting period),environmental range(i.e.,the temperature and precipitation range)and geographical range(i.e.,distribution range and altitudinal range).Ordinary least squares models and phylogenetic generalized linear mixed models were used to analyze the relationships between specimen number and the explanatory variables.Random Forest models were then used to find the most parsimonious multivariate model.The results showed that interannual variation in specimen number between 1900 and 2020 was considerable.Specimen number of these species in southeast China was notably lower than that in northwest China.Environmental range and geographical range of species had significant positive correlations with specimen number.In addition,there were relatively weak but significant associations between specimen number and species trait(i.e.,plant height and flowering and fruiting period).Random Forest models indicated that distribution range was the most important variable,followed by flowering and fruiting period,and altitudinal range.These findings suggest that future floristic surveys should pay more attention to species with small geographical range,narrow environmental range,short plant height,and short flowering and fruiting period.The correction of specimen collection preference will also make the results of species distribution model,species evolution and other works based on specimen data more accurate. 展开更多
关键词 Biological specimen Collection preference Dominant plant species Environmental range Geographical range Species traits
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